Investigating the effect of marking and delineation treatments on driver behavior at highway exit gore areas

Highway exit gore areas are common and essential components of highway networks everywhere. Drivers need to navigate, decelerate, and change lanes at exit gore areas through specified and compacted geometry. This makes exit gore areas potentially crash-prone locations. Studies analyzed factors contributing to crashes at exit gore areas. Although marking and delineation techniques can play a major role in enhancing safety, traffic control devices that serve this end were not given sufficient attention in recent research. Furthermore, the currently used marking and delineation treatments are widely different around the world and deploy devices of various forms, shapes, sizes, and colors. The Flemish Agency for Roads & Traffic (AWV) launched a study to explore the feasibility of adding colored and sizeable eye-catching objects, mounted or grounded exactly at the physical nose, to attract driver's attention and improve driving performance. The eye-tracking and driving behavior of 49 Belgian drivers was investigated in a driving simulator. Participants were also queried about the conspicuity of the control devices and their personal preferences. The results were univocal for situations including a guardrail. Using two mounted panels together, i.e., the horizontal and the vertical, scored better on all levels than the horizontal panel alone. The bigger surface size of the traffic control device significantly improved driving performance and was also favored by the participants. Situations without a guardrail lacked such clear results, which were mixed depending on the measure at hand. A larger size of a grounded object-marker, again, improved driver's performance. Findings concerning the colors red or green appeared to favor red, although this was less univocal. These findings are aimed to spark ideas for further research and to assist practitioners and policy-makers in better designing exit gore areas while achieving more consistency and safety.